Key Points
- To establish and characterize an intact, unanesthetized canine model of cardiogenic shock that accurately reproduces the hemodynamic features of human cardiogenic shock.
- Induced myocardial infarction via selective embolization of the circumflex coronary artery using 0.2 ml of mercury in intact, unanesthetized dogs.
- Monitored hemodynamic parameters—including systemic blood pressure, left ventricular end-diastolic pressure (LVEDP), pulmonary artery pressure, and cardiac output—alongside electrocardiograms until death occurred (5 to 48 hours post-embolization).
- Systemic blood pressure fell sharply to 25–30% of baseline immediately post-embolization, and cardiac output fell to 40% of control with no subsequent recovery.
- LVEDP initially stayed normal (5–10 mm Hg) before rising above 10 mm Hg, accompanied by elevated mean pulmonary artery pressures and increased peripheral resistance.
- Electrocardiography showed normal sinus rhythm with brief runs (5–15 beats) of ventricular tachycardia and AV dissociation, indicating that fatal shock stemmed from progressive mechanical pump failure rather than lethal arrhythmias.
Structured PICO
PPopulationIntact unanesthetized dogs
IInterventionSelective embolization of the circumflex coronary artery with 0.2 ml of mercury
CComparatorPre-embolization control levels
OOutcomeDevelopment of cardiogenic shock and death
Selective embolization of the circumflex coronary artery with mercury in unanesthetized dogs provides a reproducible model of cardiogenic shock.